In order to clarify whether the colorless oxidation dye intermediate mixture in the fiber is present, the timecourse
of K/S-Ramda curve of the wool fabric dyed for the different dyeing time with p-phenylenediamine (pPDA) alone,
pPDA/ p-amino-o-cresol (pAOC) and pPDA/ resorcinol (RC) dyeing system was investigated by keeping them in a
dark room at ambient temperature and humidity for 30 days. The dyeing was carried out using hydrogen peroxide as
oxidant at pH 10 and 30 degree for 30 min. In the sample dyed with pPDA alone system and pPDA/pAOC couple system
included ethylenediaminetetraacetic acid (EDTA) and ascorbic acid, the colorless oxidation dye intermediate mixture is scarcely substantive inside the fiber dyed for the different dyeing time,whereas in the sample dyed with pPDA/RC couple system included EDTA and ascorbic acid the presence of the colorless oxidation dye intermediate mixture
within the fiber was confirmed. However, the time-course of K/S-Ramda curve of the wool fabric dyed with pPDA/RC
couple system excluded EDTA and ascorbic acid indicated that there is no presence of the colorless oxidation dye
intermediate mixture inside wool fibers. On taking all the results into consideration, we reached the conclusion that the oxidation dye intermediates presented inside the wool fiber are the colorless leucoindo dyes as a discrete entity. We concluded, furthermore, that the presented leucoindo dyes result from inhibiting the oxidative reaction of the leucoindo dyes by the anti-oxidative function of ascorbic acid, and deductively that, in the greater part of the precursor/coupler dyeing system, the oxidative reaction of the leucoindo dye occurred principally at the outside regions of fiber surface
and the produced indo dye penetrated into the intercuticlar region of the wool fiber.
Cyclodextrin (CD) was fixed onto a fabric using isocyanate as a cross-linker and their durability was discussed. The CDpolymer was insoluble on water, and reaction of CD with isocyanate was characterized with infrared spectroscopy. The poly(ethylene terephthalate) fabric was dipped into a solution of Beta-CD and isocyanate, and the fabric was annealed to fix CD. Weight decrease and CD content on the fabric was followed to evaluate the wash durability of the fabric. When CD was fixed with triisocyanate showed higher durability compared with the one fixed with diisocyanate. For the fabric with the highest durability, 60% of CD remained on the fabric even after 50 times washing. Absorption capacity of the CD on the fabric was evaluated to be 80% from the adsorption of phenolphthalein on a fabric
Lac dyeing of cotton fabrics pretreated with tannic acid and aluminum acetate was investigated. Five treatment methods (tannic acid alone, aluminum alone, tannic acid -> aluminum, aluminum -> tannic acid, and tannic acid luminum ->tannic acid) before dyeing with lac were compared for their effect on adsorption of the laccaic
acid to cotton fabric. The treatment with tannic acid -> aluminum was found to be the most effective for lac dyeing of cotton. It was found that tannic acid enhanced the aluminum adsorption to cotton fabric, and the affinity of aluminum to laccaic acid enhanced the dyeing effect. The adsorption of tannic acid, aluminum and laccaic acid to cotton was quantitatively determined, and the dyeing mechanism was proposed.
Poly(γ-glutamic acid) (PGA) was crosslinked by γ-ray irradiation to produce the transparent PGA hydrogel. The effects of the molecular weight of PGA and the dosage of the γ-ray irradiation on the swelling ability and mechanical strength of the PGA hydrogel were systematically investigated. The preparation of PGA hydrogel / apatite composite was performed by soaking the hydrogel in a simulated body fluid. The hydrogel obtained from the calcium form of PGA became turbid during the soaking to form the PGA composite. The FT-IR and XRD analyses showed the formation of the crystalline apatite in the PGA hydrogel. The surface morphology of the composite was observed by SEM. Proliferation of MC3T3-E1 cells on the resulting composite was examined for application of tissue engineering scaffold.